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To enhance the sensitivity of graphene aerogel‐based piezoresistive sensors by weakening their compressive strength while keeping their elasticity, lightweight and lamellar graphene aerogels (LGAs) with high elasticity and satisfactory electrical conductance networks are fabricated by bidirectional‐freezing of aqueous suspensions of graphene oxide in the presence of small amounts of organic solvents, followed by lyophilizing and thermal annealing. Because of the lamellar structure of the LGA, its compressive strength along the direction perpendicular to the lamellar surface is much lower than those of both isotropic and unidirectionally aligned graphene aerogels with similar apparent densities, leading to an ultrasensitive LGA‐based piezoresistive sensor with a high sensitivity of −3.69 kPa−1 and a low detection limit of 0.15 Pa. The ultrahigh sensitivity and low detection limit of LGA‐based piezoresistive sensor contribute to detecting subtle pressure at room temperature and in liquid nitrogen with ability to detect dynamic force frequency and sound vibration. Besides, thanks to the fewer junction points between the graphene lamellae, LGAs slices can be integrated as a wide‐range and sensitive bending sensor, which can detect arbitrary bending angles from 0° to 180° with a low detection limit of 0.29°, and is efficient in detecting biosignals of wrist pulse and finger bending.

As the global water shortage becomes increasingly serious, it is highly imperative to develop efficient, renewable, and large-scale water purification devices. Herein, an efficient solar-driven water purification device of wood coated with Fe2O3 nanoparticle-decorated carbon nanotubes (Fe2O3/CNT) is fabricated in only a few seconds by one-step combustion of ferric acetylacetonate in an ambient environment. The thin layer of the Fe2O3/CNT hybrid coated on the upper surface of the wood serves as a solar-light absorber for converting solar energy to thermal energy, while the thermally insulating wood layer with vertically aligned channels endows the device with rapid water upward transport and localizes the generated heat inside the Fe2O3/CNT layer for solar-driven water evaporation. As a result, the wood/Fe2O3/CNT device achieves a high water steam generation capability of 1.42 kg m–2 h–1 along with an excellent evaporation efficiency of 87.2% under 1 sun irradiation, higher than most of the wood-based solar-driven water evaporation device reported. This device is also efficient in the purification of seawaters and wastewaters. This work demonstrates a rapid and facile methodology for large-scale fabrication of wood/Fe2O3/CNT devices for efficient solar-driven water purification.

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